Development of novel lightweight and cost-effective Mg-Ce-Al wrought alloy with high strength

IMPACT STATEMENT A new mechanism of linear/planar cosegregation of solutes for ultrafine DRXed grains formation in Mg alloys has been found, rather than traditional planar segregations and/or nanoprecipitations at grain boundaries. The low microalloying content and high yield strength of 365 MPa have been achieved simultaneously in extruded Mg-Ce-Al alloy which is mainly ascribed to the unexpected grain refinement (mean size of similar to 420 nm). It is found that adding tiny Al (0.05 wt.%) into Mg-0.2 wt.% Ce alloy can promote the formation of Ce-Al-enriched segregation along dislocations and grain boundaries which can effectively counterbalance the thermally activated dislocation recovery and thus guarantee grain refinement. The ultra-fined grains are mainly related to both linear and planar cosegregation of solutes, rather than the traditional planar segregations and/or nanoprecipitations at grain boundaries.

Automated summary

A new mechanism of linear/planar cosegregation of solutes has been discovered in Mg alloys, leading to ultrafine grains formation. The addition of tiny Al into Mg-Ce alloy promotes the formation of Ce-Al-enriched segregation along dislocations and grain boundaries, effectively counterbalancing thermally activated dislocation recovery and guaranteeing grain refinement. Ultra-fined grains are mainly related to both linear and planar cosegregation of solutes, rather than traditional planar segregations and/or nanoprecipitations at grain boundaries.